The Use of Compacted Tropical Clay Treated With Rice Husk Ash as a Suitable Hydraulic Barrier Material in Waste Containment Applications

Abstract

Protection of our environment from pollutants emanating from wastes generated by man made activities and disposal systems in less developed countries is now a matter of growing concern. Laboratory tests were conducted on compacted tropical clay treated with up to 16 % rice husk ash (RHA) an agro-industrial waste to access its suitability in waste containment barrier application. Soil–RHA mixtures was compacted using standard Proctor, West African Standard and modified Proctor efforts at −2, 0, 2 and 4 % of optimum moisture content. Index properties, volumetric shrinkage, hydraulic conductivity, and unconfined compressive strength tests were performed. Overall acceptable zones under which the material was suitable (low hydraulic conductivity <1 × 10−9 m/s, minimum volumetric shrinkage strain <4 % and high compressive strength > 200 kN/m2) were obtained. Results suggest the suitability of this material in waste containment barrier application for up to 8 % RHA treatment,which will ameliorate the environmental problems created by this agro-industrial waste.